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1.
Med Res Rev ; 43(4): 1038-1067, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36916676

RESUMEN

Capsaicin is a naturally occurring alkaloid derived from chili pepper that is responsible for its hot pungent taste. Capsaicin is known to exert multiple pharmacological actions, including analgesia, anticancer, anti-inflammatory, antiobesity, and antioxidant effects. The transient receptor potential vanilloid subfamily member 1 (TRPV1) is the main receptor mediating the majority of the capsaicin effects. However, numerous studies suggest that the TRPV1 receptor is not the only target for capsaicin. An increasing number of studies indicates that capsaicin, at low to mid µM ranges, not only indirectly through TRPV1-mediated Ca2+ increases, but also directly modulates the functions of voltage-gated Na+ , K+ , and Ca2+ channels, as well as ligand-gated ion channels and other ion transporters and enzymes involved in cellular excitability. These TRPV1-independent effects are mediated by alterations of the biophysical properties of the lipid membrane and subsequent modulation of the functional properties of ion channels and by direct binding of capsaicin to the channels. The present study, for the first time, systematically categorizes this diverse range of non-TRPV1 targets and discusses cellular and molecular mechanisms mediating TRPV1-independent effects of capsaicin in excitable, as well as nonexcitable cells.


Asunto(s)
Alcanfor , Capsaicina , Humanos , Capsaicina/farmacología , Transporte Iónico , Canales Catiónicos TRPV/metabolismo
2.
BMC Med Educ ; 23(1): 388, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37237263

RESUMEN

BACKGROUND: The establishment of new anatomy facilities needs to accommodate a combination of modern teaching modalities that best align with evidence-based best teaching practices. This article describes the process in which our state-of-the-art anatomy laboratories were designed and implemented, and how these facilities support aspects of modern anatomy education. METHODS: A list of best practices for anatomy education in a modern medical curriculum was summarized from the literature. To assess student satisfaction, a survey related to student perception of the anatomy facilities (5-point Likert scale) was conducted. RESULTS: Our educational modalities include a broad range of teaching approaches. The Instructional Studio houses prosected and plastinated specimens, and cadaveric dissections are performed. Each of our three Dry Laboratories allow for active learning and interaction between small student groups. The Webinar Room acts as a conference room for departmental and online meetings, discussions with students, and dialogues with affiliated hospitals via the internet. The Imaging Center is equipped with a Sectra® medical educational platform, CAE Vimedix® Virtual Medical Imaging Ultrasound Training System, and Philipps Lumify® Ultrasound devices to train students to conduct and interpret sonographic images. Moreover, the Complete Anatomy® program is made available to all our students. CONCLUSION: The layout of our newly created Anatomy Facilities allows for all aspects of modern medical education mentioned in the literature. These educational modalities and teaching approaches are highly appreciated by our faculty and students. Moreover, these technologies allowed for a smooth transition from on-site anatomy teaching to online education during the COVID pandemic.


Asunto(s)
Anatomía , COVID-19 , Educación de Pregrado en Medicina , Estudiantes de Medicina , Humanos , Educación de Pregrado en Medicina/métodos , COVID-19/epidemiología , Disección/educación , Curriculum , Evaluación Educacional/métodos , Cadáver , Anatomía/educación , Enseñanza
3.
Ann Dermatol Venereol ; 150(2): 114-120, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37270319

RESUMEN

BACKGROUND: In areas of low physician density, especially as regards dermatologists in France, there is an increasing interest in tele-expertise. This is particularly the case in the Sarthe department, where the number of physicians continues to decline and access to care was further limited by the COVID 19 epidemic. STUDY DESIGN: We retrospectively collected data from tele-expertise requests submitted to Le Mans General Hospital by general practitioners via a dedicated platform between May 6, 2019, and April 9, 2021. RESULTS: Six hundred and forty three requests relating to 90 different diagnoses were recorded during this period. One hundred and thirty four patients (20% of requests) were invited to attend a face-to-face consultation within an average of 29 days. DISCUSSION: Through the use of tele-expertise at Le Mans Genreal Hospital it was possible to introduce a means of tackling the problem of the lack of dermatologists in the Sarthe department. Rapid responses enabled the number of consultation requests to be reduced, leading to fewer population displacements in the context of the present pandemic. CONCLUSION: These initial results are encouraging and confirm that tele-expertise seems a satisfactory option to optimize access to care for populations in areas of low physician density.


Asunto(s)
COVID-19 , Médicos , Telemedicina , Masculino , Humanos , Estudios Retrospectivos , Hospitales Generales , COVID-19/epidemiología , Francia
4.
Horm Metab Res ; 54(8): 503-509, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35724689

RESUMEN

When the corona pandemic commenced more than two years ago, it was quickly recognized that people with metabolic diseases show an augmented risk of severe COVID-19 and an increased mortality compared to people without these comorbidities. Furthermore, an infection with SARS-CoV-2 has been shown to lead to an aggravation of metabolic diseases and in single cases to new-onset metabolic disorders. In addition to the increased risk for people with diabetes in the acute phase of COVID-19, this patient group also seems to be more often affected by long-COVID and to experience more long-term consequences than people without diabetes. The mechanisms behind these discrepancies between people with and without diabetes in relation to COVID-19 are not completely understood yet and will require further research and follow-up studies during the following years. In the current review, we discuss why patients with diabetes have this higher risk of developing severe COVID-19 symptoms not only in the acute phase of the disease but also in relation to long-COVID, vaccine breakthrough infections and re-infections. Furthermore, we discuss the effects of lockdown on glycemic control.


Asunto(s)
COVID-19 , Diabetes Mellitus , COVID-19/complicaciones , Control de Enfermedades Transmisibles , Diabetes Mellitus/epidemiología , Humanos , SARS-CoV-2 , Síndrome Post Agudo de COVID-19
5.
Horm Metab Res ; 54(8): 496-502, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35724688

RESUMEN

Obesity is an increasing health problem all over the world. In combination with the current COVID-19 pandemic, this has turned into a massive challenge as individuals with overweight and obesity at all ages show a significant increase in their risk of getting severe COVID-19. Around 20% of all patients that were hospitalized for COVID-19 suffered from obesity alone, whereas obesity in combination with other metabolic comorbidities, such as type 2 diabetes and hypertension, account for up to 60% of all hospitalizations in relation to COVID-19. Therefore, it is of immense importance to put the spotlight on the high incidence of obesity present already in childhood both by changing the individual minds and by encouraging politicians and the whole society to commence preventive interventions for achieving a better nutrition for all social classes all over the world. In the current review, we aim to explain the different pathways and mechanisms that are responsible for the increased risk of severe COVID-19 in people with overweight and obesity. Furthermore, we discuss how the pandemic has led to weight gains in many people during lockdown. At the end, we discuss the importance of preventing such an interface between a non-communicable disease like obesity and a communicable disease like COVID-19 in the future.


Asunto(s)
COVID-19 , Diabetes Mellitus Tipo 2 , COVID-19/epidemiología , Control de Enfermedades Transmisibles , Diabetes Mellitus Tipo 2/epidemiología , Humanos , Obesidad/complicaciones , Obesidad/epidemiología , Sobrepeso , Pandemias/prevención & control
6.
Ann Dermatol Venereol ; 149(4): 228-237, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36229262

RESUMEN

BACKGROUND: The objective of this literature review was to list the different etiologies of macroglossia reported in the literature, to identify characteristics that might guide diagnosis, and to create a diagnostic algorithm. METHODS: The bibliographic search was carried out between October 2019 and July 2020 in the PubMed research base using the keywords "macroglossia" (MESH) and/or "tongue enlargement". RESULTS: Of the 1711 references identified, 615 articles were excluded, and 1096 abstracts were reviewed. We classified the different etiologies identified according to their mechanism and whether they were congenital or acquired. The etiologies are divided into the following categories: genetic malformation syndromes, non-syndromic congenital malformations, endocrinopathies, neuromuscular diseases, storage disorders, infectious, inflammatory, traumatic, and iatrogenic diseases. CONCLUSION: Based on this review, we propose a diagnostic algorithm for macroglossia according to the characteristics described. The most common diagnoses among acquired causes were amyloidosis (13.7%), endocrinopathies (8.8%), myopathies (4%) and tongue tumors (6.7%). The most common congenital causes were aneuploidy, lymphatic malformations, and Beckwith-Wiedemann syndrome, which is the main cause of congenital macroglossia, even if it appears isolated.


Asunto(s)
Macroglosia , Humanos , Algoritmos , Síndrome de Beckwith-Wiedemann/complicaciones , Macroglosia/diagnóstico
7.
J Anat ; 239(5): 973-982, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34164802

RESUMEN

Trauma, corticosteroid therapy and metabolic diseases are well established aetiologies of humeral head osteonecrosis; however, there is increasing evidence that arthroscopic rotator cuff surgery may be another possible cause. One of the reasons is that there may be inadvertent damage to the arterial blood supply to the humeral head during surgical intervention. The blood supply to the humeral head displays large amounts of variation with regard to origin, course and distribution. Therefore, to shed light on the pathogenesis, the blood supply of the humeral head is reviewed together with a summary of all reported cases of osteonecrosis of the humeral head that occurred following rotator cuff repair. Inconsistencies with regard to terminologies used and contradictions concerning arterial contributions from the anterior circumflex humeral artery and the posterior circumflex humeral artery towards humeral head supply are addressed. Moreover, variations in the course of the anterior circumflex humeral artery and its branches are summarized. The vascular anatomy of the humeral head is clinically relevant due to the close relationship of these blood vessels with the surgical repair sites for rotator cuff surgery and biceps tenotomies or tenodesis procedures. Potential sites of disruption of blood supply following arthroscopic rotator cuff surgery are discussed. Detailed knowledge of the course of the arteries supplying the humeral head may help to minimize the risk of vascular injury and subsequent osteonecrosis. Given the great interindividual variations of vascular anatomy, imaging procedures preceding arthroscopic rotator cuff surgery may be advisable.


Asunto(s)
Osteonecrosis , Lesiones del Manguito de los Rotadores , Artroscopía , Humanos , Cabeza Humeral , Osteonecrosis/etiología , Manguito de los Rotadores/cirugía
8.
Int J Mol Sci ; 22(14)2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34298871

RESUMEN

Autistic spectrum disorder (ASD) refers to a group of neurodevelopmental disorders characterized by impaired social interaction and cognitive deficit, restricted repetitive behaviors, altered immune responses, and imbalanced oxidative stress status. In recent years, there has been a growing interest in studying the role of nicotinic acetylcholine receptors (nAChRs), specifically α7-nAChRs, in the CNS. Influence of agonists for α7-nAChRs on the cognitive behavior, learning, and memory formation has been demonstrated in neuro-pathological condition such as ASD and attention-deficit hyperactivity disorder (ADHD). Curcumin (CUR), the active compound of the spice turmeric, has been shown to act as a positive allosteric modulator of α7-nAChRs. Here we hypothesize that CUR, acting through α7-nAChRs, influences the neuropathology of ASD. In patch clamp studies, fast inward currents activated by choline, a selective agonist of α7-nAChRs, were significantly potentiated by CUR. Moreover, choline induced enhancement of spontaneous inhibitory postsynaptic currents was markedly increased in the presence of CUR. Furthermore, CUR (25, 50, and 100 mg/kg, i.p.) ameliorated dose-dependent social deficits without affecting locomotor activity or anxiety-like behaviors of tested male Black and Tan BRachyury (BTBR) mice. In addition, CUR (50 and 100 mg/kg, i.p.) mitigated oxidative stress status by restoring the decreased levels of superoxide dismutase (SOD) and catalase (CAT) in the hippocampus and the cerebellum of treated mice. Collectively, the observed results indicate that CUR potentiates α7-nAChRs in native central nervous system neurons, mitigates disturbed oxidative stress, and alleviates ASD-like features in BTBR mice used as an idiopathic rodent model of ASD, and may represent a promising novel pharmacological strategy for ASD treatment.


Asunto(s)
Trastorno del Espectro Autista/tratamiento farmacológico , Trastorno del Espectro Autista/metabolismo , Trastorno Autístico/tratamiento farmacológico , Curcumina/farmacología , Hipocampo/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Regulación Alostérica/efectos de los fármacos , Animales , Trastorno Autístico/metabolismo , Colina/farmacología , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Agonistas Nicotínicos/farmacología , Conducta Social
9.
Int J Mol Sci ; 22(6)2021 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-33802843

RESUMEN

Poisoning with organophosphorus compounds (OPCs) represents an ongoing threat to civilians and rescue personal. We have previously shown that oximes, when administered prophylactically before exposure to the OPC paraoxon, are able to protect from its toxic effects. In the present study, we have assessed to what degree experimental (K-27; K-48; K-53; K-74; K-75) or established oximes (pralidoxime, obidoxime), when given as pretreatment at an equitoxic dosage of 25% of LD01, are able to reduce mortality induced by the OPC azinphos-methyl. Their efficacy was compared with that of pyridostigmine, the only FDA-approved substance for such prophylaxis. Efficacy was quantified in rats by Cox analysis, calculating the relative risk of death (RR), with RR=1 for the reference group given only azinphos-methyl, but no prophylaxis. All tested compounds significantly (p ≤ 0.05) reduced azinphos-methyl-induced mortality. In addition, the efficacy of all tested experimental and established oximes except K-53 was significantly superior to the FDA-approved compound pyridostigmine. Best protection was observed for the oximes K-48 (RR = 0.20), K-27 (RR = 0.23), and obidoxime (RR = 0.21), which were significantly more efficacious than pralidoxime and pyridostigmine. The second-best group of prophylactic compounds consisted of K-74 (RR = 0.26), K-75 (RR = 0.35) and pralidoxime (RR = 0.37), which were significantly more efficacious than pyridostigmine. Pretreatment with K-53 (RR = 0.37) and pyridostigmine (RR = 0.52) was the least efficacious. Our present data, together with previous results on other OPCs, indicate that the experimental oximes K-27 and K-48 are very promising pretreatment compounds. When penetration into the brain is undesirable, obidoxime is the most efficacious prophylactic agent already approved for clinical use.


Asunto(s)
Azinfosmetilo/toxicidad , Oximas/farmacología , Animales , Azinfosmetilo/química , Inhibidores de la Colinesterasa/farmacología , Concentración 50 Inhibidora , Peso Molecular , Compuestos Organofosforados/química , Compuestos Organofosforados/toxicidad , Plaguicidas/química , Plaguicidas/toxicidad , Modelos de Riesgos Proporcionales , Ratas Wistar , Riesgo , Análisis de Supervivencia
10.
Ann Dermatol Venereol ; 148(3): 156-160, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33487487

RESUMEN

INTRODUCTION: Simulation in healthcare is a rapidly developing teaching method in the training of technical procedures. It is also used to enable caregivers to learn how to inform patients of serious illness and complex health status. However, its use is not widespread in the field of dermatology. This study investigated the utility of simulation as regards disclosing melanoma diagnosis, taking resident physician satisfaction as a primary endpoint. MATERIALS AND METHODS: Fifteen dermatology residents were recruited as trainees. Four scenarios were allocated based on length of residency. An introductory briefing was held prior to the training sessions. Debriefing took place on completion of the diagnosis disclosure consultation. The participants completed questionnaires after the simulation session, after debriefing, and 3 months after the simulation session. The primary endpoint was usefulness of the session felt by trainees several months after the simulation. RESULTS: The majority of participants (93.3%) thought the session helped with stress management, improved their attitude and control over their reaction (86.6%), and improved their communication skills (100%). They rated the usefulness of the simulation at 7.79/10 on average (range: 5-10). DISCUSSION: According to our findings the resident physicians involved, particularly those with the least experience, were satisfied with this type of learning technique. Any difficulties encountered by these residents were brought to light and addressed during debriefing. CONCLUSION: There would appear to be real benefits to be reaped from simulation, whatever the stage of medical training at which it takes place. Simulation should become an increasingly important part of contemporary pregraduate specialty programs.


Asunto(s)
Dermatología , Internado y Residencia , Competencia Clínica , Comunicación , Humanos , Encuestas y Cuestionarios
11.
Molecules ; 25(7)2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32230733

RESUMEN

AIMS: Organophosphates (OPCs), useful agents as pesticides, also represent a serious health hazard. Standard therapy with atropine and established oxime-type enzyme reactivators is unsatisfactory. Experimental data indicate that superior therapeutic results can be obtained when reversible cholinesterase inhibitors are administered before OPC exposure. Comparing the protective efficacy of five such cholinesterase inhibitors (physostigmine, pyridostigmine, ranitidine, tacrine, or K-27), we observed best protection for the experimental oxime K-27. The present study was undertaken in order to determine if additional administration of K-27 immediately after OPC (paraoxon) exposure can improve the outcome. METHODS: Therapeutic efficacy was assessed in rats by determining the relative risk of death (RR) by Cox survival analysis over a period of 48 h. Animals that received only pretreatment and paraoxon were compared with those that had received pretreatment and paraoxon followed by K-27 immediately after paraoxon exposure. RESULTS: Best protection from paraoxon-induced mortality was observed after pretreatment with physostigmine (RR = 0.30) and K-27 (RR = 0.34). Both substances were significantly more efficacious than tacrine (RR = 0.67), ranitidine (RR = 0.72), and pyridostigmine (RR = 0.76), which were less efficacious but still significantly reduced the RR compared to the no-treatment group (paraoxon only). Additional administration of K-27 immediately after paraoxon exposure (posttreatment) did not further reduce mortality. Statistical analysis between pretreatment before paraoxon exposure alone and pretreatment plus K-27 posttreatment did not show any significant difference for any of the pretreatment regimens. CONCLUSIONS: Best outcome is achieved if physostigmine or K-27 are administered prophylactically before exposure to sublethal paraoxon dosages. Therapeutic outcome is not further improved by additional oxime therapy immediately thereafter.


Asunto(s)
Inhibidores de la Colinesterasa/administración & dosificación , Inhibidores de la Colinesterasa/toxicidad , Reactivadores de la Colinesterasa/farmacología , Paraoxon/toxicidad , Animales , Masculino , Organofosfatos/toxicidad , Oximas/administración & dosificación , Oximas/química , Paraoxon/química , Fisostigmina/administración & dosificación , Fisostigmina/química , Profilaxis Posexposición , Profilaxis Pre-Exposición , Modelos de Riesgos Proporcionales , Bromuro de Piridostigmina/administración & dosificación , Bromuro de Piridostigmina/química , Ranitidina/química , Ranitidina/farmacología , Ratas , Ratas Wistar , Análisis de Supervivencia , Tacrina/administración & dosificación , Tacrina/química
12.
Int J Cosmet Sci ; 42(5): 421-428, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32390187

RESUMEN

In 2017, Cosmetics Europe performed a double-blinded ring test of 24 emulsion-type sunscreen products, across 3 in vivo test laboratories and 3 in vitro test laboratories, using a new candidate in vitro SPF test method. Based on the results of this work, an article was published showing how data derived from a new lead candidate method conform to new International Standards (ISO) acceptance criteria for alternative SPF test methods (Any alternative method should consider the matrix effect and if required, specify the matrix applicability of the method; Criterion 1a: Systematic differences between methods should be negligible: 95% of all individual results of an alternative method are within the range of ±2× reproducibility standard deviation of the in vivo method, that is overall bias must be below 0.5× reproducibility standard deviation of the in vivo method; Criterion 1b: Measurement uncertainty of an alternative method should be below the measurement uncertainty of the in vivo method. Candidate method predicted values must fall within the full 'funnel' (SPF 6-50+) limits proposed by Cosmetics Europe (derived from the same minimum test design, that is using the ISO24444 Method to measure at least 24 products across at least 3 laboratories using at least 5 test subjects/laboratory, in a blinded fashion).). Of the 24 sunscreen products tested, the majority of emulsions were of the oil-in-water (O/W) type, whereas only one was water-in-oil (W/O) and there were no products with a mineral-only sun filter system. In order to confirm the scope of this method, therefore, a new study was conducted that included 73 W/O (12 mineral + organic, 44 mineral only and 17 organic only) and 3 O/W mineral-only, emulsion-type sunscreen products (a total of 76 new sunscreen products). When combined with the previous 24 products (tested in 3 different laboratories), this yielded a new data set comprising a total of 100 emulsion-type sunscreen products, with SPF values ranging from 6 to 50+ (with a total of 148 data points). These products were tested using the double-plate in vitro SPF test method and compared with the ISO TC217/WG7 acceptance criteria for alternative SPF test methods. Over 95% of paired in vitro: in vivo SPF values lay within the upper and lower limits of the ISO acceptance criteria funnel, with no bias. This new in vitro SPF test method, therefore, meets the minimum requirements for an alternative SPF test method to ISO24444:2010, for emulsion-type sunscreen products (which make up the majority of marketed sunscreen products).


En 2017, Cosmetics Europe a réalisé un ring test en double aveugle de 24 produits de protection solaire de type émulsion, dans 3 laboratoires de test in vivo et 3 laboratoires de test in vitro, en utilisant une nouvelle méthode de test SPF in vitro. Sur la base des résultats de ces travaux, un article a été publié montrant comment les données dérivées de cette nouvelle méthode sont conformes aux nouveaux critères d'acceptation des normes internationales (ISO) pour les méthodes de test SPF alternatives. Sur les 24 produits de protection solaire testés, la majorité des émulsions étaient du type huile dans l'eau (H / E), tandis qu'un seul était de l'eau dans l'huile (E / H) et il n'y avait aucun produit contenant uniquement des minéraux. Afin de confirmer cette méthode, une nouvelle étude a donc été menée comprenant 73 produits E/ H (12 produits contenant des filtres minéraux + organiques, 44 produits contenant des filtres minéraux uniquement et 17 produits contenant des filtres organiques uniquement) et 3 produits H / E contenant des filtres minéraux uniquement, tous de type émulsion (donc un un total de 76 nouveaux produits de protection solaire). Combiné aux 24 produits précédents (testés dans 3 laboratoires différents), cela a donné un nouvel ensemble de données comprenant un total de 100 produits de protection solaire de type émulsion, avec des valeurs SPF allant de 6 à 50+ (avec un total de 148 points de données) . Ces produits ont été testés à l'aide de la méthode de test SPF in vitro double approche et comparés aux critères d'acceptation de l'ISO TC217 / WG7 pour les méthodes alternatives du SPF in vivo. Plus de 95% des valeurs de SPF appariées in vitro: in vivo se situent dans les limites supérieure et inférieure de l'entonnoir des critères d'acceptation ISO, sans biais. Cette nouvelle méthode de test SPF in vitro, par conséquent, répond aux exigences minimales d'une méthode de test SPF alternative à ISO24444: 2010, pour les produits de protection solaire de type émulsion (qui constituent la majorité des produits de protection solaire commercialisés).


Asunto(s)
Emulsiones , Protectores contra Radiación , Factor de Protección Solar , Protectores Solares , Técnicas In Vitro
13.
J Appl Toxicol ; 39(1): 101-116, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30027640

RESUMEN

Organophosphorus compounds (OPCs), inhibitors of acetylcholinesterase (AChE), are useful agents as pesticides, but also represent a serious health hazard. Standard therapy with atropine and established oxime-type enzyme reactivators (pralidoxime, obidoxime) is unsatisfactory. Better therapeutic results are obtained, when reversible AChE inhibitors are administered before OPC exposure. This review summarizes the history of such a pretreatment approach and sums up a set of experiments undertaken in search of compounds that are efficacious when given before a broad range of OPCs. The prophylactic efficacy of 10 known AChE inhibitors, either already used clinically for different indications (physostigmine, pyridostigmine, ranitidine, tiapride, tacrine, amiloride, metoclopramide, methylene blue) or developed for possible therapeutic use in the future (7-methoxytacrine, K-27) was compared, when administered before exposure to six chemically diverse OPCs in the same experimental setting: ethyl-paraoxon, methyl-paraoxon, diisopropylfluorophosphate, terbufos sulfone, azinphos-methyl and dicrotophos. The experimental oxime K-27 was the most efficacious compound, affording best protection, when administered before terbufos sulfone, azinphos-methyl and dicrotophos, second best before ethyl- and methyl-paraoxon exposure and third best before diisopropylfluorophosphate administration. This ranking was similar to that of physostigmine, which was superior to the Food and Drug Administration-approved pretreatment for soman with pyridostigmine. Tiapride, amiloride, metoclopramide, methylene blue and 7-methoxytacrine did not achieve protection. No correlation was observed between the IC50 of the reversible AChE inhibitors and their protective efficacy. These studies indicate that K-27 can be considered a very promising broad-spectrum prophylactic agent in case of imminent organophosphate exposure, which may be related to its AChE reactivating activity rather than its AChE inhibition.


Asunto(s)
Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Intoxicación por Organofosfatos/tratamiento farmacológico , Intoxicación por Organofosfatos/prevención & control , Organofosfatos/toxicidad , Profilaxis Pre-Exposición/métodos , Animales , Humanos , Modelos Animales
14.
J Appl Toxicol ; 39(11): 1506-1515, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31264735

RESUMEN

Organophosphates, useful agents as pesticides, also represent a serious danger due to their high acute toxicity. There is indication that oximes, when administered before organophosphate exposure, can protect from these toxic effects. We have tested at equitoxic dosage (25% of LD01 ) the prophylactic efficacy of five experimental (K-48, K-53, K-74, K-75, K-203) and two established oximes (pralidoxime and obidoxime) to protect from mortality induced by the organophosphate paraoxon. Mortalities were quantified by Cox analysis and compared with those observed after pretreatment with a strong acetylcholinesterase inhibitor (10-methylacridine) and after the FDA-approved pretreatment compound pyridostigmine. All nine tested substances statistically significantly reduced paraoxon-induced mortality. Best protection was conferred by the experimental oxime K-48, reducing the relative risk of death (RR) to 0.10, which was statistically significantly superior to pyridostigmine (RR = 0.31). The other oximes reduced the RR to 0.13 (obidoxime), 0.20 (K-203), 0.21 (K-74), 0.24 (K-75) and 0.26 (pralidoxime), which were significantly more efficacious than 10-methylacridine (RR = 0.65). These data support the hypothesis that protective efficacy is not primarily due to cholinesterase inhibition and indicate that the tested experimental oximes may be considered promising alternatives to the established pretreatment compound pyridostigmine.


Asunto(s)
Reactivadores de la Colinesterasa/farmacología , Cloruro de Obidoxima/farmacología , Paraoxon/toxicidad , Compuestos de Pralidoxima/farmacología , Sustancias Protectoras/farmacología , Animales , Reactivadores de la Colinesterasa/administración & dosificación , Dosificación Letal Mediana , Masculino , Cloruro de Obidoxima/administración & dosificación , Paraoxon/química , Compuestos de Pralidoxima/administración & dosificación , Modelos de Riesgos Proporcionales , Sustancias Protectoras/administración & dosificación , Ratas Wistar , Análisis de Supervivencia
15.
Int J Cosmet Sci ; 41(3): 320-324, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31087383

RESUMEN

OBJECTIVE: The Sun Protection Factor (SPF) of sunscreen products is derived from testing in vivo their ability to prevent erythema ("sunburn"). Recently, certain articles have raised concerns that sunscreen products may actively suppress erythema via anti-inflammatory / anti-oxidant (AI/AO) activity. These articles reason that this may result in a higher labelled SPF value than that provided by the efficacy of the UVR filters alone, giving consumers a "false sense of security". On the other hand, since inflammatory processes are known to play a role in the mechanisms of photodamage / skin cancer induction and propagation, AI/AO activity may provide valuable incremental photoprotective benefit (provided that there is no interference with visible erythema). The objective of these studies, therefore, was to investigate the potential of AI/AO ingredients to suppress UVR-induced erythemal response in human skin, in vivo. METHODS: In vivo studies with SPF30 sunscreen formulations containing a variety of AI/AO ingredients were performed according to the International Standard ISO24444:2010 method. While ISO24444:2010 requires assessment of erythema at 20 ± 4h post-irradiation, an additional assessment at 5 h post-irradiation was also used to determine potential delay in erythema development. RESULTS: None of the formulations, containing a variety of AI/AO ingredients, influenced SPF determination in comparison to the vehicle formulation. CONCLUSION: Our in vivo results demonstrate that commonly-used AI/AO ingredients, at concentrations typically used in sunscreen products, neither influence SPF value nor delay erythemal response, i.e., the measured SPF reflects the true photoprotective capacity of the product.


OBJECTIF: Le facteur de protection solaire (SPF) des produits de protection solaire est dérivé de tests in vivo servant à déterminer leur capacité à prévenir un érythème (« coup de soleil ¼). Récemment, certains articles ont soulevé des inquiétudes en insinuant que les produits de protection solaire pourraient activement faire disparaître un érythème par le biais d'une activité anti-inflammatoire/anti-oxydante (AI/AO). Ces articles soutiennent que cela pourrait impliquer une valeur déclarée du SPF plus élevée que celle fournie par l'efficacité des filtres RUV à eux seuls, donnant ainsi une « fausse impression de sécurité ¼ aux consommateurs. D'autre part, étant donné que les processus inflammatoires sont réputés jouer un rôle dans les mécanismes de photo-altération/d'induction et de propagation du cancer de la peau, l'activité AI/AO pourrait apporter un précieux bénéfice photo-protecteur amplifié (à condition qu'il n'y ait aucune interférence avec un érythème visible). L'objectif de ces études était, par conséquent, d'étudier le potentiel des ingrédients contribuant à l'activité AI/AO à faire disparaître la réponse érythémateuse induite par les RUV dans la peau humaine, in vivo. MÉTHODES: Des études in vivo avec des formules de produits solaires à SPF30 contenant une variété d'ingrédients contribuant à l'activité AI/AO ont été effectuées conformément à la méthode correspondant à la norme internationale ISO24444:2010. Bien que l'ISO24444:2010 nécessite l'évaluation de l'érythème à 20 _ 4 heures post-irradiation, une évaluation supplémentaire à 5 heures post-irradiation a également été utilisée pour déterminer l'éventuel délai d'apparition d'un érythème. RÉSULTATS: Aucune des formules, contenant une variété d'ingrédients contribuant à l'activité AI/AO, n'a influencé la détermination du SPF par comparaison à la formule véhicule. CONCLUSION: Nos résultats in vivo démontrent que les ingrédients contribuant à l'activité AI/AO fréquemment utilisés, aux concentrations généralement utilisées dans les produits de protection solaire, n'influencent pas la valeur du SPF, pas plus qu'ils ne retardent la réponse érythémateuse, autrement dit, le SPF mesuré reflète la véritable capacité photo-protectrice du produit.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Protectores Solares/química , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Piel/efectos de los fármacos , Piel/efectos de la radiación , Factor de Protección Solar , Rayos Ultravioleta
16.
Int J Cosmet Sci ; 2018 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-29676800

RESUMEN

OBJECTIVE: The objective of this work was to investigate the utility of a new in vitro SPF test method in blinded ring-testing, against new ISO acceptance criteria. METHODS: Twenty four blinded, commercial, emulsion-type, primary sunscreen products, covering the full range of labelled SPF in Europe (SPF6 - 50+), were tested by three test institutes using the current ISO24444:2010 In Vivo SPF Test Method and simultaneously by three separate test laboratories using a new candidate in vitro SPF test method, developed under the leadership of Cosmetics Europe (CE). The resulting relationship between in vitro SPF and in vivo SPF values was then compared with acceptance criteria developed recently by the International Standards (ISO) TC217/WG7 Sun Protection Test Methods Working Group. RESULTS: Analysis of the mean inter-laboratory in vitro and mean inter-institute in vivo SPF values revealed a strong correlation between in vitro and in vivo values, with a Pearson correlation coefficient of r2  = 0.88 (P < 0.0001), a slope of 1.01 and a non-significant intercept (-1.48; P = 0.62). When these data were compared to the new ISO WG7 acceptance criteria, method bias was found to be extremely low and over 95% of the coupled data lay within the model 'funnel' (defined by upper and lower confidence intervals). CONCLUSION: In conclusion, the results of blinded ring testing and comparison to new ISO WG7 acceptance criteria indicate that a new in vitro SPF test method meets (and exceeds) these minimum criteria and is an interesting candidate for possible deployment as an industry test methodology.

17.
J Appl Toxicol ; 37(1): 13-22, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27612208

RESUMEN

The recognition in the early 1960s by Morifusa Eto that tri-o-cresyl phosphate (TOCP) is hydroxylated by the cytochrome P450 system to an intermediate that spontaneously cyclizes to a neurotoxic phosphate (saligenin phosphate ester) ignited the interest in this group of compounds. Only the ortho isomer can cyclize and clinically cause Organo Phosphate Induced Delayed Neurotoxicity (OPIDN); the meta and para isomers of tri-cresyl phosphate are not neuropathic because they are unable to form stable cyclic saligenin phosphate esters. This review identifies the diverse biological effects associated with various cyclic and caged phosphates and phosphonates and their possible use. Cyclic compounds that inhibit acetylcholine esterase (AChE), such as salithion, can be employed as pesticides. Others are neurotoxic, most probably because of inhibition of neuropathy target esterase (NTE). Cyclic phosphates that inhibit lipases, the cyclipostins, possibly represent promising therapeutic avenues for the treatment of type 2 diabetes mellitus and/or microbial infections; those compounds inhibiting ß-lactamase may prevent bacterial resistance against ß-lactam antibiotics. Naturally occurring cyclic phosphates, such as cyclic AMP, cyclic phosphatidic acid and the ryanodine receptor modulator cyclic adenosine diphosphate ribose, play an important physiological role in signal transduction. Moreover, some cyclic phosphates are GABA-antagonists, while others are an essential component of Molybdenum-containing enzymes. Some cyclic phosphates (cyclophosphamide, ifosfamide) are clinically used in tumor therapy, while the coupling of therapeutic agents with other cyclic phosphates (HepDirect® Technology) allows drugs to be targeted to specific organs. Possible clinical applications of these compounds are considered. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Descubrimiento de Drogas/métodos , Compuestos Organofosforados/química , Compuestos Organofosforados/farmacología , Animales , Ciclización , Humanos , Estructura Molecular , Relación Estructura-Actividad
18.
J Appl Toxicol ; 35(2): 219-27, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24853289

RESUMEN

Unforeseen toxic effects contribute to compound attrition during preclinical evaluation and clinical trials. Consequently, there is a need to correlate in vitro toxicity to in vivo and clinical outcomes quickly and effectively. We propose an expedited evaluation of physiological parameters in vitro that will improve the ability to predict in vivo toxicity of potential therapeutics. By monitoring metabolism, mitochondrial physiology and cell viability, our approach provides insight to the extent of drug toxicity in vitro. To implement our approach, we used human hepatocellular carcinoma cells (HepG2) and neuroblastoma cells (SH-SY5Y) to monitor hepato- and neurotoxicity of the experimental oxime K027. We utilized a trivalent approach to measure metabolism, mitochondrial stress and induction of apoptosis in 96-well formats. Any change in these three areas may suggest drug-induced toxicity in vivo. K027 and pralidoxime, an oxime currently in clinical use, had no effect on glycolysis or oxygen consumption in HepG2 and SH-SY5Y cells. Similarly, these oximes did not induce oxidant generation nor alter mitochondrial membrane potential. Further, K027 and pralidoxime failed to activate effector caspases, and these oximes did not alter viability. The chemotherapeutic agent, docetaxel, negatively affected metabolism, mitochondrial physiology and viability. Our studies present a streamlined high-throughput trivalent approach for predicting toxicity in vitro, and this approach reveals that K027 has no measurable hepatotoxicity or neurotoxicity in vitro, which correlates with their in vivo data. This approach could eliminate toxic drugs from consideration for in vivo preclinical evaluation faster than existing toxicity prediction panels and ultimately prevent unnecessary experimentation.


Asunto(s)
Células Hep G2/efectos de los fármacos , Oximas/toxicidad , Compuestos de Piridinio/toxicidad , Apoptosis/efectos de los fármacos , Encéfalo/efectos de los fármacos , Caspasas/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Docetaxel , Glucólisis/efectos de los fármacos , Humanos , Hígado/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Neuroblastoma/metabolismo , Compuestos de Pralidoxima/toxicidad , Taxoides/toxicidad , Pruebas de Toxicidad/métodos , Células Tumorales Cultivadas/efectos de los fármacos
19.
J Appl Toxicol ; 35(5): 493-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25186309

RESUMEN

Pre-treatment with reversible acetylcholinesterase (AChE) inhibitors before organophosphorous compound (OPC) exposure can reduce OPC-induced mortality. However, pyridostigmine, the only substance employed for such prophylaxis, is merely efficacious against a limited number of OPCs. In search of more efficacious and broad-range alternatives, we have compared in vivo the ability of five reversible AChE inhibitors (pyridostigmine, physostigmine, ranitidine, tacrine and K-27) to reduce mortality induced by the OPC azinphos-methyl. Protection was quantified using Cox analysis by determining the relative risk (RR) of death in rats that were administered these AChE inhibitors in equitoxic dosage (25% of LD01) 30 min before azinphos-methyl exposure. Azinphos-methyl-induced mortality was significantly reduced by all five tested compounds as compared with the reference group that was only exposed to azinphos-methyl without prior pre-treatment (RR = 1). The most efficacious prophylactic agents were K-27 (RR = 0.15) and physostigmine (RR = 0.21), being significantly more efficacious than ranitidine (RR = 0.62) and pyridostigmine (RR = 0.37). Pre-treatment with tacrine (RR = 0.29) was significantly more efficacious than pre-treatment with ranitidine, but the difference between tacrine and pyridostigmine was not significant. Our results indicate that prophylactic administration of the oxime K-27 may be a promising alternative in cases of imminent OPC exposure.


Asunto(s)
Azinfosmetilo/toxicidad , Inhibidores de la Colinesterasa/farmacología , Animales , Relación Dosis-Respuesta a Droga , Masculino , Oximas/farmacología , Fisostigmina/farmacología , Modelos de Riesgos Proporcionales , Compuestos de Piridinio/farmacología , Bromuro de Piridostigmina/farmacología , Ranitidina/farmacología , Ratas , Ratas Wistar , Tacrina/farmacología
20.
Arterioscler Thromb Vasc Biol ; 33(5): 1014-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23448970

RESUMEN

OBJECTIVE: We demonstrated that inflammatory cells and intima-media thickening are increased in carotids exposed to low-blood flow in the SJL/J (SJL) strain compared with other mouse strains. We hypothesized that the extent of inflammation associated with intima-media thickening is a genetically regulated trait. APPROACH AND RESULTS: We performed a whole genome approach to measure leukocyte infiltration in the carotid intima as a quantitative trait in a genetic cross between C3HeB/FeJ (C3H/F) and SJL mice. Immunostaining for CD45(+) (a pan-specific leukocyte marker) was performed on carotids from C3H/F, SJL, F1, and N2 progeny to measure leukocyte infiltration. We identified a nearly significant quantitative trait locus for CD45(+) on chromosome (chr) 11 (17 cM, LOD=2.3; significance was considered at threshold P=0.05). Interval mapping showed that the CD45(+) locus on chr 11 accounted for 8% of the variation in the logarithm of odds backcross. Importantly, the CD45(+) locus colocalized with the intima-modifier 2 (Im2) locus, which controls 17% of intima variation. We created 2 Im2 congenic lines of mice (C3H/F.SJL.11.1 and C3H/F.SJL.11.2) to better understand the regulation of intima-media thickening by the chr 11 locus. The C3H/F.SJL.11.1 congenic mouse showed ≈30% of the SJL trait, confirming that CD45(+) cell infiltration contributed to the intima trait. CONCLUSIONS: We discovered a novel locus on chr 11 that controls leukocyte infiltration in the carotid. Importantly, this locus overlaps with our previously published Im2 locus on chr 11. Our study reveals a potential mechanistic relationship between leukocyte infiltration and intima-media thickening in response to decreased blood flow.


Asunto(s)
Arterias Carótidas/patología , Cromosomas de los Mamíferos , Leucocitos/fisiología , Sitios de Carácter Cuantitativo , Túnica Íntima/patología , Actinas/análisis , Animales , Movimiento Celular , Femenino , Antígenos Comunes de Leucocito/análisis , Masculino , Ratones , Ratones Endogámicos C3H
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